class Rails::Dom::Testing::Assertions::SelectorAssertions::SubstitutionContext

def initialize
  @substitute = "?"
end

def match(matches, attribute, matcher)
  matches.find_all { |node| node[attribute] =~ Regexp.new(matcher) }
end

def matcher_for(value, format_for_presentation)
  # Nokogiri doesn't like arbitrary values without quotes, hence inspect.
  if format_for_presentation
    value.inspect # Avoid to_s so Regexps aren't put in quotes.
  elsif value.is_a?(Regexp)
    "\"#{value}\""
  else
    value.to_s.inspect
  end
end

def substitutable?(value)
  [ Symbol, Numeric, String, Regexp ].any? { |type| value.is_a? type }
end

def substitute!(selector, values, format_for_presentation = false)
  selector.gsub @substitute do |match|
    next match[0] if values.empty? || !substitutable?(values.first)
    matcher_for(values.shift, format_for_presentation)
  end
end